Karen Wynn (born Dec 18, 1962) is a Canadian and American Professor of Psychology and Cognitive Science at Yale University.[1] She was born in Austin, Texas and grew up on the Canadian prairies in Regina, Saskatchewan. Her research explores the cognitive capacities of infants and young children. She directs the Infant Cognition Laboratory in the Psychology Department at Yale University.

Karen Wynn is known for her pioneering work on infants' and children's early numerical cognition. Some of her most influential research on this topic, published in the scientific journal Nature in 1992, reported that 5-month-old human infants are able to compute the outcomes of simple addition and subtraction operations on small sets of physical objects.[2][3] "Psychologists were stunned when Wynn announced her results, and many skeptical researchers around the world devised variants of her procedure to determine whether her conclusions were correct."[4] Wynn's findings were subsequently replicated by independent researchers in the United States and in Europe on human infants[5][6] and later extended to other subject populations, including rhesus monkeys[7] and domesticated dogs[8][9] who, like human babies, distinguished correct from incorrect outcomes of additions and subtractions of objects (eggplants, in the studies with rhesus monkeys; doggie biscuits, in the studies with dogs).

Wynn has suggested that humans, along with many other animal species, are innately endowed with cognitive machinery for detecting and reasoning about numbers of items.

Wynn has also investigated humans' early social preferences and judgments. Some of this research, conducted with collaborators Paul Bloom and J. Kiley Hamlin, found that 6- and 10-month-old infants distinguish helpful from unhelpful characters in simple interactions enacted by hand puppets, and prefer the helping characters to the hinderers.[10][11] Notable philosopher of bioethics Peter Singer wrote of these studies that they “have upset the previous wisdom, associated with such stellar figures in psychology as Sigmund Freud, Jean Piaget, and Lawrence Kohlberg, that human moral development is the product of our rearing and our culture.”[12]
Wynn and her colleagues have suggested that babies’ tendency to prefer prosocial individuals may arise from an adaptive capacity to detect good candidate partners for reciprocal interactions, and to distinguish such individuals from, and prefer them to, those who may be more likely to act in self-interest or to renege on implied social contracts.